Numerous processes for the determination of a position are known. Here measurements can be made on the basis of the signal-run time or the phase. In most cases, several measurements are carried out on signals or signal portions with different frequencies for the determination of a position, which signals or signal portions are received successively or simultaneously. For example, satellite based processes are known which are able to determine a position by an evaluation of radio signals. This is how on the basis of several measurements and the corresponding differences, position changes or respectively speeds, when taking into consideration the time periods elapsed between said measurements, can be determined.
Furthermore, also a determination of the relative speed is possible on the basis of the Doppler-effect.
It is also known, by means of so-called inertial sensors, to detect movements or respectively accelerations and to calculate such speeds or respectively distances as integrals and thus to detect corresponding changes which have taken place.
Many corresponding combinations of the described systems are known.